International Coronavirus Networks Collection

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection has caused a pandemic with tens of millions of cases and more than a million deaths. The infection causes COVID-19, a disease of the respiratory system of divergent severity. No treatment exists. Epigallocatechin-3-gallate (EGCG), the major component of green tea, has several beneficial properties, including antiviral activities. Therefore, we examined whether EGCG has antiviral activity against SARS-CoV-2. EGCG blocked not only the entry of SARS-CoV-2, but also MERS- and SARS-CoV pseudotyped lentiviral vectors and inhibited virus infections in vitro. Mechanistically, inhibition of the SARS-CoV-2 spike–receptor interaction was observed. Thus, EGCG might be suitable for use as a lead structure to develop more effective anti-COVID-19 drugs.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), emerged at the end of 2019 and by mid-June 2020 the virus had spread to at least 215 countries, caused more than 8 000 000 confirmed infections and over 450 000 deaths, and overwhelmed healthcare systems worldwide. Like severe acute respiratory syndrome coronavirus (SARS-CoV), which emerged in 2002 and caused a similar disease, SARS-CoV-2 is a betacoronavirus. Both viruses use human angiotensin-converting enzyme 2 (hACE2) as a receptor to enter cells. However, the SARS-CoV-2 spike (S) glycoprotein has a novel insertion that generates a putative furin cleavage signal and this has been postulated to expand the host range. Two low-passage (P) strains of SARS-CoV-2 (Wash1 : P4 and Munich : P1) were cultured twice in Vero E6 cells and characterized virologically. Sanger and MinION sequencing demonstrated significant deletions in the furin cleavage signal of Wash1 : P6 and minor variants in the Munich : P3 strain. Cleavage of the S glycoprotein in SARS-CoV-2-infected Vero E6 cell lysates was inefficient even when an intact furin cleavage signal was present. Indirect immunofluorescence demonstrated that the S glycoprotein reached the cell surface. Since the S protein is a major antigenic target for the development of neutralizing antibodies, we investigated the development of neutralizing antibody titres in serial serum samples obtained from COVID-19 human patients. These were comparable regardless of the presence of an intact or deleted furin cleavage signal. These studies illustrate the need to characterize virus stocks meticulously prior to performing either in vitro or in vivo pathogenesis studies.

The sudden emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019 from the Chinese province of Hubei and its subsequent pandemic spread highlight the importance of understanding the full molecular details of coronavirus infection and pathogenesis. Here, we compared a variety of replication features of SARS-CoV-2 and SARS-CoV and analysed the cytopathology caused by the two closely related viruses in the commonly used Vero E6 cell line. Compared to SARS-CoV, SARS-CoV-2 generated higher levels of intracellular viral RNA, but strikingly about 50-fold less infectious viral progeny was recovered from the culture medium. Immunofluorescence microscopy of SARS-CoV-2-infected cells established extensive cross-reactivity of antisera previously raised against a variety of non-structural proteins, membrane and nucleocapsid protein of SARS-CoV. Electron microscopy revealed that the ultrastructural changes induced by the two SARS viruses are very similar and occur within comparable time frames after infection. Furthermore, we determined that the sensitivity of the two viruses to three established inhibitors of coronavirus replication (remdesivir, alisporivir and chloroquine) is very similar, but that SARS-CoV-2 infection was substantially more sensitive to pre-treatment of cells with pegylated interferon alpha. An important difference between the two viruses is the fact that – upon passaging in Vero E6 cells – SARS-CoV-2 apparently is under strong selection pressure to acquire adaptive mutations in its spike protein gene. These mutations change or delete a putative furin-like cleavage site in the region connecting the S1 and S2 domains and result in a very prominent phenotypic change in plaque assays.

Introduction. Coronavirus disease 2019 (COVID-19) is an infectious disease caused by Severe Acute Respiratory Corona Virus-2 (SARS-CoV-2). The disease was first identified in December 2019 in Wuhan, the capital of China's Hubei province, and has since spread globally, resulting in the ongoing 2019–2020 corona virus pandemic. SARS-CoV-2 is closely related to the original SARS-CoV. It is thought to have a zoonotic origin. The virus is primarily spread between people during close contact, often via small droplets produced by coughing, sneezing or talking. People may also become infected by touching a contaminated surface and then touching their face. COVID-19 patients currently remain the primary source of infection. An epidemiological survey indicated that the general population is susceptible to SARS-CoV-2. The spectrum of this disease ranges from mild to life-threatening. Fever is the most common symptom, although older people and those with comorbidities may experience fever later in the disease. Other common symptoms include cough, loss of appetite, fatigue, shortness of breath, sputum production, and muscle and joint pains. Symptoms such as nausea, vomiting and diarrhea have been observed in varying percentages. Some cases might progress promptly to acute respiratory distress syndrome (ARDS) and/or multiple organ function failure. Asymptomatic carriers and those in the incubation period may also be infectious.

Aim. To determine the epidemiological and clinical characteristics of patients presenting with COVID-19 at the screening clinic of a tertiary care hospital in Peshawar, Pakistan.

Methodology. In this descriptive study, we analysed data of patients presenting to a newly established Covid-19 screening clinic in Rehman Medical Institute. Anyone who reported with new onset fever and/or cough was tested for SARS-CoV-2 in the screening clinic. We documented and analysed demographic, epidemiological and clinical characteristics, which included age, sex, travel history, clinical features, comorbidities and laboratory data of patients confirmed by real-time reverse-transcription (RT)-PCR at Rehman Medical Institute, Peshawar, Pakistan from 15 March till 21 April 2020. Paired specimens of throat swabs and nasal swabs were obtained from 845 patients, ribonucleic acid (RNA) was extracted and tested for SARS-CoV-2 by the RT-PCR assay.

Results. A total of 845 specimens were taken as described above. The positive rate for SARS-CoV-2 was about 14.3%. Male and older population had a significantly higher positive rate. Of the 121 patients infected with SARS-CoV-2, the mean age was 43.19 years (sd, 17.57) and the infections were more frequent among male gender accounting for 85 (70.25 %) patients. Common symptoms included fever (88 patients, 72 %), cough (72 patients, 59.5 %) and shortness of breath (69 patients, 57 %). Twenty-two (18 %) patients had recent travel history outside Pakistan in the previous 14 days, the majority of whom had returned back from Saudi Arabia.

Conclusion. In this single-centre, prospective, descriptive study, fever, cough and shortness of breath were the most common symptoms. Old age (>50 years), chronic underlying comorbidities and travel history may be risk factors. Therefore, we concluded that viral nucleic acid amplification tests (NAAT) played an important role in identifying SARS-CoV-2 infection in a screening clinic, which helped with isolation and cohorting of these patients.

UK Biobank (UKB) is an international health resource enabling research into the genetic and lifestyle determinants of common diseases of middle and older age. It comprises 500 000 participants. Public Health England’s Second Generation Surveillance System is a centralized microbiology database covering English clinical diagnostics laboratories that provides national surveillance of legally notifiable infections, bacterial isolations and antimicrobial resistance. We previously developed secure, pseudonymized, individual-level linkage of these systems. In this study, we implemented rapid dynamic linkage, which allows us to provide a regular feed of new COVID-19 (SARS-CoV-2) test results to UKB to facilitate rapid and urgent research into the epidemiological and human genetic risk factors for severe infection in the cohort. Here, we have characterized the first 1352 cases of COVID-19 in UKB participants, of whom 895 met our working definition of severe COVID-19 as inpatients hospitalized on or after 16 March 2020. We found that the incidence of severe COVID-19 among UKB cases was 27.4 % lower than the general population in England, although this difference varied significantly by age and sex. The total number of UKB cases could be estimated as 0.6 % of the publicly announced number of cases in England. We considered how increasing case numbers will affect the power of genome-wide association studies. This new dynamic linkage system has further potential to facilitate the investigation of other infections and the prospective collection of microbiological cultures to create a microbiological biobank (bugbank) for studying the interaction of environment, human and microbial genetics on infection in the UKB cohort.